Sleep is a fundamental aspect of human life and a vital health necessity for restoring the body’s balance and well-being after a long, exhausting day. It also gives the brain a chance to rest and regain clarity. While sleep typically occurs during the night, it can also happen at other times, especially after consuming a meal, particularly a heavy one. This often leads to yawning and drowsiness, almost as if the food contains a sedative. This phenomenon seems contrary to the fact that food is supposed to provide energy. Therefore, it raises the question of why we feel sleepy after eating.
Doctors explain that post-meal drowsiness is due to a series of processes that occur in the digestive system and body. One contributing factor is the fluctuation in blood sugar levels. When we eat sugary foods, blood sugar levels can rise and then drop rapidly, leading to sudden fatigue. However, this is not the only factor to consider, as hormones also play a role. After eating, there can be an increase in the production and release of serotonin, commonly known as the “happiness hormone.” This hormone plays a significant role in our mood and sleep cycles, but elevated levels can lead to increased drowsiness. Researchers believe that higher serotonin levels may be responsible for this effect.
Certain foods contribute to drowsiness, especially those rich in an amino acid called tryptophan, which is involved in producing serotonin. Foods high in protein, such as cheese, eggs, and turkey, contain tryptophan. Additionally, some foods, like cherries, can affect melatonin levels, which may enhance sleep. For instance, milk with high melatonin levels is sometimes recommended to improve sleep. A 2015 study suggested that melatonin is linked to biological rhythms, including core body temperature and sleep-wake cycles. Drowsiness or a sense of mental fog, sometimes called “brain fog,” after a meal is also common among individuals with food sensitivities or those suffering from a condition known as small intestinal bacterial overgrowth (SIBO).
While research has not yet provided a definitive answer to why we sometimes feel sleepy after eating, doctors recommend some steps to boost afternoon productivity and avoid sluggishness. Incorporating fiber-rich foods into meals can help stabilize blood sugar levels and prevent the crash that leads to drowsiness. Regular meals and avoiding excessively large portions can also prevent overloading the digestive system, which can contribute to fatigue and lethargy.
